Effects of Water Absorption on Creep Behavior of Wood—Plastic Composites

Abstract

The effects of filler loading and immersion in water on the creep/ recovery behavior of composites made from MDF (medium density fiberboard) flour (as natural fiber) and recycled HDPE (high density polyethylene) (as resin) were studied (at 60, 70, and 80% by weight fiber loadings). Nominal density and dimensions of the manufactured panels were 1 g/cm3 and 35 × 35 × 1 cm3, respectively. Maximum values of flexural modulus and strength of panels were obtained at 70 and 60% fiber content, respectively. The creep strain decreased as the lignocellulosic flour level increased. Water absorption has negative effect on creep behavior of MDF flour/HDPE composites. For all filler contents, it can be seen that the creep strain increases when the immersion time increases. This is believed to occur as a result of the cumulative effect of absorbed water on fiber matrix debonding and easier relaxation of the molecules at higher moisture contents leading to larger deformations at longer times.

Studies on Mechanical Performance of Wood-Plastic Composites: Polystyrene-Eucalyptus globulus Labill

“…Furthermore, WPCs are more resistant against the attack of fungus and have a good dimensional stability under humidity exposure (Clemons 2002;Yang et al 2006). The water absorption capacity was affected by the nature of the wood particles and the thermoplastic matrix (Saeed et al 2008). Ideally, the polymeric matrix embeds the wood particles completely, avoiding contact between the water and the particles.…”

Influence of the stress level and hygrothermal conditions on the creep/recovery behaviour of high-grade flax and hemp fibre reinforced GreenPoxy matrix composites

“…This knowledge is, however, essential for ensuring a reliable design in various field applications. While the creep behaviour of short fibre composites is quite well documented [20][21][22][23][24], unfortunately, the number of scientific articles focused on the creep behaviour of long fibre composites is limited [12,[25][26][27][28][29]. However, plant fibres, such as hemp and flax, exhibit pronounced viscoelastic behaviour, even in the longitudinal direction [30,31].…”

Development of HDPE/natural fiberboard nanocomposite reinforced Bi2O3/BaO and H3BO3: A sustainable approach for gamma and neutron shielding application

“…Alireza et al investigated the water absorption (WA) of the MDF, average WA of the samples ranged from 73.7% to 92.7% for 24 h immersion 48 . The value of water absorption of 40% MDF flour/HDPE composite blended in a laboratory mixer at 1500 rpm for 5 min was around 5% 49 …”

“…48 The value of water absorption of 40% MDF flour/HDPE composite blended in a laboratory mixer at 1500 rpm for 5 min was around 5%. 49 T A B L E 2 Thermal stability properties of HDPE and HDPE/NF nanocomposites.…”